Search results for "Neutralizing"

Homotypic Protection Against Rotavirus-Induced Diarrhea in Infant Mice Breast-Fed by Dams Immunized with the Recombinant VP8* Subunit of the VP4 Caps…

2000

The outer capsid proteins VP4 and VP7 induce neutralizing antibody against rotavirus. We have investigated in a mouse model the protection mediated by immunization with VP8*, the amino-terminal tryptic fragment of VP4. BALB/c female mice immunized with simian rotavirus SA11 VP6 and VP8* proteins expressed in Escherichia coli were mated with seronegative males. Litters were orally challenged with the SA11 strain (P5B[2], G3) or with the murine rotavirus strain EDIM (P10[16], G3) to verify the degree of protection against diarrhea induced in the newborns. Only those pups born to dams immunized with VP8* did not develop diarrhea after having been orally challenged with the SA11 strain. Pups bo…

2019

Abstract Type B Coxsackieviruses (CVBs) belong to the enterovirus genus, and they cause both acute and chronic diseases in humans. CVB infections usually lead to flu-like symptoms but can also result in more serious diseases such as myocarditis, aseptic meningitis and life-threatening multi-organ infections in young infants. Thus, CVBs have long been considered as important targets of future vaccines. We have previously observed CVB1 capsid disintegration and virus concentration decrease with 12-day long formalin inactivation protocol. Here a scalable ion exchange chromatography purification method was developed, and purified CVB1 was inactivated with UV-C or formalin. Virus morphology and …

Regression of advanced rat and human gliomas by local or systemic treatment with oncolytic parvovirus H-1 in rat models

2010

Oncolytic virotherapy is a potential treatment modality under investigation for various malignancies including malignant brain tumors. Unlike some other natural or modified viruses that show oncolytic activity against cerebral neoplasms, the rodent parvovirus H-1 (H-1PV) is completely apathogenic in humans. H-1PV efficiently kills a number of tumor cells without harm to corresponding normal ones. In this study, the concept of H-1PV-based virotherapy of glioma was tested for rat (RG-2 cell-derived) and for human (U87 cell-derived) gliomas in immunocompetent and immunodeficient rat models, respectively. Large orthotopic rat and human glioma cell-derived tumors were treated with either single …

N-terminal myristoylation-dependent masking of neutralizing epitopes in the preS1 attachment site of hepatitis B virus

2011

The N-terminally myristoylated preS1 domain of the large hepatitis B surface protein (LHBs) mediates specific attachment of hepatitis B virus (HBV) to hepatocytes. Its B-cell epitopes leading to neutralization of infectivity are not yet characterized.We inserted C- and N-terminal preS1 peptides into the most immunogenic region of HBV core particles, therewith immunized Balb/c mice and determined binding properties and neutralization potential of resulting antibodies in vitro.The particles with preS1 inserts were highly immunogenic and the corresponding anti-preS antibodies strongly bound to HBV particles from chronic carriers infected with different HBV genotypes A-F. However, antibodies bi…

Optimized recombinant dense bodies of human cytomegalovirus efficiently prime virus specific lymphocytes and neutralizing antibodies without the addi…

2010

Control of human cytomegalovirus (HCMV) infection correlates with the reconstitution of antiviral T lymphocytes in haematopoietic stem cell transplant recipients. A vaccine to foster this reconstitution and to ameliorate the severe consequences of HCMV reactivation is yet unavailable. This work focused on providing a rationale for the amendment of the yields and the antigenic composition of a vaccine, based on subviral dense bodies (DB) of HCMV. Modified DB were generated that contained the HLA-A2 presented IE1 model peptide TMYGGISLL, integrated at different positions in the major DB protein pp65. Insertion at position W175 of pp65 allowed efficient formation of recDB in the cytoplasm of i…

Lack of association between the kinetics of human cytomegalovirus (HCMV) glycoprotein B (gB)-specific and neutralizing serum antibodies and developme…

2001

The kinetics of the gB-specific and neutralizing antibody responses to human cytomegalovirus (HCMV) were analyzed in 26 allogeneic stem-cell transplant recipients who either did (n = 20) or did not (n = 6) develop asymptomatic HCMV active infection during the study period. Antibody response profiles varied widely among individuals in both groups, irrespective of whether HCMV active infection did or did not occur. Development of HCMV active infection was not preceded by a decline in functional serum antibody levels. Neither the absence nor the presence of HCMV active infection correlated with either high or low serum levels of gB-specific and neutralizing antibodies, respectively. In most pa…

Modulation of epitope-specific anti-hepatitis C virus E2 (anti-HCV/E2) antibodies by antiviral treatment

2006

The dynamic features of three specific anti-hepatitis C virus (HCV) antibody subpopulations directed against different conformational epitopes of the viral E2 protein (HCV/E2) have been evaluated in patients with primary and persistent HCV infection; the three subpopulations are present in patients infected with different HCV genotypes and have shown a different activity using a pseudovirus neutralization assay (antibodies e301 and e137 exhibiting high neutralizing activity, while antibody e509 enhancement of HCV infectivity). In sequential samples from five patients with primary HCV infection and different virological outcome, all samples tested negative with the single exception of the e5…

Dense Bodies of a gH/gL/UL128/UL130/UL131 Pentamer-Repaired Towne Strain of Human Cytomegalovirus Induce an Enhanced Neutralizing Antibody Response

2019

The development of a vaccine against human cytomegalovirus infection (HCMV) is a high-priority medical goal. The viral pentameric protein complex consisting of glycoprotein H (gH)/gL/UL128-131A (PC) is considered to be an important vaccine component. Its relevance to the induction of a protective antibody response is, however, still a matter of debate. We addressed this issue by using subviral dense bodies (DBs) of HCMV. DBs are exceptionally immunogenic. Laboratory HCMV strain DBs harbor important neutralizing antibody targets, like the glycoproteins B, H, L, M, and N, but they are devoid of the PC. To be able to directly compare the impact of the PC on the levels of neutralizing antibody …

COVID-19 in people living with HIV: Clinical implications of dynamics of the immune response to SARS-CoV-2.

2020

ABSTRACT Background Little evidence on COVID‐19 in people living with HIV (PLWH) is currently available. Material and Methods We reported clinical and viro‐immunological data of all HIV‐positive patients admitted to our centre with COVID‐19 from March 1 to May 12,2020. Results Overall, five patients were included: all were virologically‐suppressed on antiretroviral therapy and CD4+ count was >350 cell/mm3 in all but two patients. Although all patients had evidence of pneumonia on admission, only one developed respiratory failure. SARS‐CoV‐2‐RNA was never detected from nasopharyngeal swabs in two patients, whereas, in the others, viral clearance occurred within a maximum of 43 days. IgG prod…

A novel rat CVB1-VP1 monoclonal antibody 3A6 detects a broad range of enteroviruses

2018

AbstractEnteroviruses (EVs) are common RNA viruses that cause diseases ranging from rash to paralytic poliomyelitis. For example, EV-A and EV-C viruses cause hand-foot and mouth disease and EV-B viruses cause encephalitis and myocarditis, which can result in severe morbidity and mortality. While new vaccines and treatments for EVs are under development, methods for studying and diagnosing EV infections are still limited and therefore new diagnostic tools are required. Our aim was to produce and characterize new antibodies that work in multiple applications and detect EVs in tissues and in vitro. Rats were immunized with Coxsackievirus B1 capsid protein VP1 and hybridomas were produced. Hybr…